Method of sealing bags



Jan. 30, 1951 A. E. ALMGREN ET AL 2,539,390

METHOD OF SEALING BAGS Filed Dec. r1, 194'. 2 Sheets-Sheet 1 ATTOR EYS Jan. 30, 1951 A. E. ALMGREN ETAL 2,539,390

METHOD OF SEALING BAGS Filed Dec. 17, 1947 2 Sheets-Sheet 2 A! ATTORNEYS Patented Jan. 30, 1951 METHOD OF SEALING BAGS Augustv Almgren, Hillside, and John P. Jakob,

Roselle, N. .L, assignors to American "Gan Company, New York, N. Y., a corporation of New Jersey Application December 17, 1947, Serial No. 792,125

Claims.

This invention relates to a method of sealing bags or other flexible containers and has particular reference to a :novel method of folding together and sealing marginal edge portions of an open end of a bag filled with articles such as cans or containers. This is a companion application to our copending United States applications Serial Number 792,122, filed December 17, 1947, on Sealing Head mechanism for Closing and Sealing Bags and Containers; :Serial Number 192,123yfi1ed December 17, 1947 on Ba Sealing Machine; and Serial Number 792,124, .filed December 1 7,, 1947 on Bag- Sealing Machine.

An object of the invention is the provision of .a method of folding and sealing an open end of a bag or flexible container filled with articles such as can-s wherein the marginal edge portions of thebag adjacent its open end are turned or folded inwardly at the corners independently of the intermediate or side portions soas to cheat .a. neat appearing overlapping corner assembly Another object of the invention is the provision of such a method wherein the marginal edge portions of the open end of a bag are folded inwardlyat the corners in a pleated. fashion which results in a. smooth corner construction which may be readily sealed. when sealing the bag.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the followin description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

Figure 1 is a perspective view illustrating the open upper end of a bag filled with cans preparamy to being sealed by method steps embodying the present invention, with parts broken away; 2 is a View similar, to, Fig.1 showing the bag sealed; 7

- Fig. 3 is'a top plan view of a bag being sealed and parts of the apparatus used in sealin the Fig. 4 is an enlarged sectional view showing a pleated corner. fold taken substantially along the line 4-4 in Fig- 2; and

Figs. .5 to Binclusive are perspective views show- 'ing a fragment, at the. upper corner of a bag and illustrating how its marginal edge portions are folded and sealed in accordance with the method steps of the present invention, the views illustrating parts of the apparatus in various positions for carrying out the method steps.

As a "preferred form of the instant invention, the drawings illustrate tmethod steps or Sealing a haze! flexible container A or-rectangular-crosssection, preferably made of fibre and filled with cans B for shipment or storage. Bag A at its upper end, is provided with a marginal edge portion C which includes corner sections D and straight side sections E2 which are folded inward- 1y against a top sheet or closure member F having a band of adhesive or glue G on its top surface to seal the bag in accordance with the method steps of the invention.

In the sealing of the bag A, the closure member F is first inserted into the bag on top of the cans B as shown in Fig. 1. The corner sections D of the marginal edge "portions C, are then folded inwardly against the inserted closure member F as shown in Fig. 5. This is followed by the inward folding of the side sections E of the marginal edge portion C, while the corner portions D are held down, the terminal ends of the side sections E overlapping the corner portions D as at J, K

(Figs. 4 and 63 In order to form a smooth corner construction, theoverl'apped' portions J, K now are creased or pressed downwardly against the corner port'i'ens D to form corner pleats (Figs. 2 and 4) prepara'tory to final sealing of the bag. With the corner sections D and side sections E of the marginal edge portion 0 in this folded over position, they are pressed tightly against the closure member F to insure proper bonding of these parts throughthe medium of the adhesive or glue G on the closure member. This seals the bag in a neat appearing and" strong end construction as best shown in Fig. '2.

'One form of apparatus for carrying out the sealing of the marginal edge portion C of the bag in accordance with the instant method is a seal ing head [0 (Fig. 3) which includes a plurality of corner folding elements il and side folding elements l2 carried in a rectangular shaped head frame 13 made to fit over the open top end of a bag to be sealed.

The corner folding elements ll (see also Figs. 5, 6, '7 and 8) are located adjacent the corners of the rectangular frame 13 and are substantially triangular in outline. There are four of these corner folding elements ll, one for each corner of the bag to be sealed. These elements are 'formed' on arms 14 having long hubs i5 mounted on pins [6, carried in bearing lugs i! which project inwardly from the head frame [3. The corner folding elements II are rocked on their pins l6 simultaneouslyand toward and-away from the bag, in any suitable manner. 7

When the-corner'rolding elements It rockinward or toward theme-A. they engage thecorn'er sections D of the marginal edge portion C of the bag, and bend and fold them inwardly and downwardly against the adhesive coated portion of the closure member F, as best shown in Fig. 5. The corner folding elements remain in this position and hold the corner sections D in their folded over position while the side sections '15? of the marginal edge portion C of the bag are folded into position.

The side folding elements 12 provided for folding in the side sections E, are located along the sides of the head frame it. There are four of these side folding elements and they are formed on arms 2! having long hubs 22 which are mounted on pins 23 carried in bearing lugs 24 projectin inwardly from the head frame l3. These side folding elements are rocked simultaneouslyv on their pins 23, in any suitable manner toward and away from a bag in the sealing head In. in time with the other moving parts of the head.

When the side folding elements l2 rock toward the marginal edge portion C of the bag they engage and fold the side sections-E inwardly and downwardly against the adhesive coated portion of the closure member F and hold these side sec- K of the side sections E and thus produces a neat fiat corner pleat'as best shown in Figs. 2 and 4.

Thefolding elements H, I2 remain in position against the folded marginal edge portion C and thus hold or clamp this edge portion in engagement with the closure F for a predetermined period of time, depending upon the setting time of the adhesive being used, to insure proper bonding of the parts together. This seals the bag.

If desired this holding operation may be effected by an auxiliary clamp member or sealing pad 3| (Figs. 3 and 8) which may be moved into clamping position against the folded marginal edge portion '0, in any suitable manner. The pad is designed to fit freely within the area defined by the inner edges of the folding elements I I, I2 as best shown in Fig. 3 and thereby permits of the positioning of the pad while the folding elements are in clamping position. As soon as the pad is in place the folding elements may be lifted out of the way, as best shown in Fig. 8,

in readiness for the folding operations on a subsequent bag. The pad may be removed when the glue is set. This completes the bag sealing operations.

It is thought that theinvention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the steps ofthe process described and their order or accomplishment without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the process hereinbefore de- .described being merely a preferred embodiment thereof.

Weclaim: 1. A method of folding the ends of tubular members for containers, which comprises folding 4. 1;ai h siesse sa wi e en are aalese portion of a tubular member adjacent and surrounding an open end thereof, folding in and holding side sections of said marginal edge por-- tion intermediate said corner sections while continuing to hold said corner sections, said corner sections and said side sections being arranged in lapped relation, releasing said hold on said corner sections while continuing to hold said side sections and pressing said folded corner and said folded side sections together.

2. The method of folding and sealing bags, flexible containers and the like filled with articles, comprising folding in corner sections of a marginal edge portion surrounding the open end of a bag against an inserted closure member, holding said corner sections in their folded-in positions, folding in side sections of said marginal edge portion against said closure member intermediate the adjacent held corner portions and overlapping said folded-in corner sections, releasing said hold on said folded-in corner sections and simultaneously holding said side sections in their folded-in position overlapping the corners, and pressing said folded corner sections and said overlapping folded side sections together against said closure member and securing them thereto to seal the bag and to form pleats at the corners of the ag.

3. The method of folding and sealing bags, flexible containers and the like filled with articles such as cans, comprising folding in and holding corner sections of a mar inal edge portion surrounding the open end of a bag against an inserted closure m mber, folding in side sections of said marginal edge portion against said closure member intermediate adjacent corner sections to form corner pleats, releasing said hold on said folded-in corner sections and simultaneously holdin said side sections in their folded-in position, creasing said corner pleats, and pressing said folded corner sections and said folded side sections toget er and against said closure member and securing them thereto to seal the bag.

i. The method of folding and sealing bags, flexible containers and the like filled with articles such as cans, comprising folding in corner sections of a marginal edge portion surrounding the open end of a bag against an inserted closure member having an adhesive applied thereto, holding said corner sections in their folded-in position against said closure member, folding in side sections of said marginal edge portion intermediate the adjacent held corner sections against said closure member and against said corner sections in overlapping relation thereto, releasing said hold on said folded-in corner sections and simultaneously holding said side sections in their foldedin overlapped relation on said corner sections, and simultaneously pressing said folded-in corner and said folded-in side sections against said closure member to seal the bag.

5. The method of folding and sealing bags, flexible containers and the like filled with articles such as cans, comprising folding in corner sections of a marginal edge portion surrounding the open end of a bag against an inserted closure member having an adhesive applied thereto, holding said corner sections in their folded-in position against said closure member, folding in side sections of said marginal edge portion intermediate adjacent corner sections against said closure member and against said corner sections fie e x r ei reasses ed b.9 9 n-" a s 6 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Peters Apr. 30, 1946 Number 

